Spring construction



May 12, 1959 Filed April 28, 1955 H c. FLINT SPRING CONSTRUCTION 2 Sheets-Sheet 1 uvmvrox.

BY W rwmas'Ks.

May 12, 1959 Filed Aoril 28, 1955 H. C. FLINT SPRING CONSTRUCTION 2 Sheets-Sheet 2 INVENTOR.

U d ,sw sP tch o 2,886,311 SPRING CONSTRUCTION Hyland 'C, Flint, Birmingham, Mich., assignor to American Metal Products Company, Detroit, Mich., a corporation of Michigan 4 a Application April 28, 1955, Serial No. 504,627

8 (Ilaims. (Cl. 267-1) This invention relates tospring elements, and particularly to a spring element having a straight central wire portion and attaching end portions.

Spring strips of various types have been employed heretofore in the art for seating. More recently sinuous strips were employed made of wire bent back and forth providing uniform loops joined by straight portions. While such types of spring strips provided satisfactory support in seat and back cushions, the present type of spring element substantially reduces the length of wire required in its construction. A wire is formed at the front end to provide an attaching end having a desirable degree of resiliency and depth as required for leg support adjacent to the knees. From the front supporting end a straight section of wire extends rearwardly, forming a main load supporting portion. The rear endis formed in a manner to provide a desired degree of resiliency and an attaching end constructed in such manner as to relieve the straight section and prevent any set occurring therein. The wires forming the load supporting portion are spaced a substantial distance apart when the elements are mounted on a frame, leaving wide openings therebetween. The feel of such wires when a cushion is occupied is eliminated by the use of an insulator made up of parallel wires which are placed thereover to extend transversely of the straight sections of the spring elements. On top of the insulator, padding which may be cotton, felt, sponge rubber or the like, is added before the trim material is applied to complete the cushion thus constructed.

Accordingly, the main objects of the invention are: to provide a spring element having a central load bearing portion of straight wire section terminating at each end with a resilient portion having attaching means; .to form a spring element of wire having a straight section the front end of which extends downwardly and is formed into a resilient supporting portion of substantialheight having an attaching end, with the rear end formed as a loop terminating in an attaching end; to provide a spring element having a straight central wire portion which terurinates at thefront and rear ends in a'downwalr'dly inwardly extending formed portion p'r'oviding resiliency to the spring element, and, in general, to provide a spring element made from a minimum length of wire which is simple in construction and economical of manufacture.

Other objects and features of novelty of the invention will be specifically pointed out or will become apparent when referring, for a better understanding of the invention, to the following description taken in conjunction with the accompanying drawings, wherein:

Figure 1 is a plan view of a seat cushion having spring strips therein which embody features of the present invention;

Fig. 2 is an enlarged sectional view of the structure illustrated in Fig. 1, taken on the line 2--2 thereof;

Fig. 3 is a plan view of the spring illustrated in the cushion of Figs. 1 and 2;

Fig. 4 is a perspective view of the spring, similar to that illustrated in Fig. 3, showing a modified form thereof;

2,886,311 C rali nt a May 12,1959

5 is a plan view of the structure illustrated in 1g. I 6 is a view of structure, similar to that illustrated 1n Fig. 3, showing a further form which the invention may assume; I,

7 is a side view of the spring strip illustrated in Fig. 8 is a view of a spring strip having'a' front end as illustrated in the spring of 'Fig. 6 and a rear end as illustrated in the spring of Fig. 5, and

Fig. 9 is a side view in elevation of the spring strip i illustrated in Fig. 8.

Referring to the drawings, a cushion 10 is illustrated in Figs. 1 and 2 embodying a rectangular frame 11, on the front transverse member 12 of which a securing strip 13 is. mounted having a plurality of tubular portions 14 thereon. The rear transverse frame member 15 has a strip 16 thereon containing elongated tunnels 17 for rigidly supporting the rear end of a spring element. The spring element 18, as illustrated in Figs. 1 to 4, is made of a wire having a diagonal straight central section 19 which is the load bearing portion of the element. At the front end, the wire of the' section 19 terminates in a transverse bar 21 from which the wire slopes downwardly at 22 at a predetermined angleand is extended ata g'r'ea'ter angle at 23.. The wire is further extendedin a reverse direction to form a bar 24 and then reversely extended to form loops 25 and 26 which terminate in an arcuate loop 27 and a securing'endj28. The'end 28 is anchored 'in'a tubular portion 14, with the loop 27 resting upon a flange of the strip 13 to prevent the loop portions 25 and 26 from pivoting downwardly. The fixing of the loops 25 and 26 against downwarddeflection provides'strength.

to the forward portion of the section'19 land limits its deflection in accordance .with the'weightapplied'there' to. The deflection is further'controlled after the portion' 23 rests upon the loop 25, both of which become in activated so that thereafter the load is applied .directly through the portion 22 and the loop 26. v p .At the rearend, the section 19 is offset downwardly and laterally to form a loop 31 whic'hfpermits the supported portion of the spring to be extended lengthwise 1 to relieve the section 19 from direct strain which would cause a set therein. Theend of the loop 31.terminates in an arcuate loop 27 and straight portion 28 which is em ployedfor securing the loop end 31 ofthe spring to the transverse frame member 15. The loop 27 slides with in the elongated tubular portion 17 and fixes the end of the'loop' against pivoting either upwardly or downwardly. A' 'plurality ofthe spring strips are secured.v across the transverse frame members 12 and 15,,after which an insulator 32 is'applied thereover, the insulator embodying a plurality of wires 33 which span the seetions-19 and1 hereb P ovide a l p e t lg' sur ae 'ia wtetf e' reaa i wire-sections 19 of the strips. pad 34is applied to the insulator 33 and trim material 35 is applied over the pad in the conventional manner. The section 19 may have a kink 36 therein adjacent to the forward edge to provide a desired arc to the resulting seat construction.

In Figs. 4 and 5 a further form of spring element 37 is illustrated having the front end portion 38 the same as that of the spring element 18, with the load bearing wire section 39 disposed centrally of the front end portion 38 through the provision of a formed portion 41 which embodies the portions 25, 26, 27 and 28 of the structure illustrated in Fig. 3. At the rear end the section 39 is formed into a loop 42 and extended downwardly at 43 from which a loop 44 is formed having a laterally extending attaching end portion 45. 'In this arrangement, a V-shaped end portion in profile is provided on extension of the wire portion 39 to avoid set, but also permits the end of the loop 42'td deflect downwardly relative to the supporting end 45.

A furth enform of spring element 46 is illustrated in Figs; 6' and 7, thatwherein'the' straight central section 47 has the front end 48 rectangularly coiled and angularly disposed to be of W1 shape in profile, with the end arm 49 formed intoa U-shaped attaching end 51. The opposite endof the section 47 is sloped downwardly from the point 52 and further" shaped to provide oppositely disposed loops 53 and 54. The loop 54 has the end thereof extended upwardly at 55 and extended outwardly at 56 to form an attaching end. The attaching end 56 and the extended portion 55 function as a hanger for the end of loops 53"and 54' at the rear end of the element, permitting the portion 55 to pivot forwardly when the main load bearing section 47 is occupied. I

A further? form of spring element 57 is illustrated in Figs. 8'- and 9, that wherein the straight central section 58 terminates in a coiledfront portion59 which is substantially' of" W shape in profile having a U-shaped attaching. end portion 61-. The section 58 is bent at 62 to slope downwardly and the rear end is provided with loops 42 and 44' the same as the rear end of the spring element 37, providing a Z-shaped end which permits downward and forward movement to the rear end of the wire section 58 of the spring element. d

All of the spring element's herein illustrated have a central load bearing section which is a straight wire portion disposed between two end formed portions which provide support and resiliency thereto. At the forward end of. the section, the wire is extended downwardly and inwardly and formed to provide depth and resiliency to the resulting supporting portion. The rear end of the section has the wire formed into loops to permit the longitudinal extension of the load bearing section, which loops may be formed into Z shape in profile to permit the rear end of the section to deflect downwardly. The resiliency at the ends of the straight central load bearing section prevents overstressing and the setting thereof under. load so that thc section will at all times maintain a desired contour to the cushion.

What is claimed is:

1. A spring element made of wire having a straight wire section forming the load supporting portion of the element, a formed portion beneath the forward end of the section having substantial depth which provides resiliency to the forward end of the section, and a laterally extendingv loop atthe rear of the section providing resiliency longitudinally of the section, said loop having a laterally extending torsion bar portion.

2. A spring element made of wire having a straight wire section forming the load supporting portion of the element, a formed portion beneath the forward end of the section having. substantial depth which provides resiliency to the forward end of the section, a laterally extending loop at the rear of the section providing resiliency longitudinally ofthe section, said loop having a 4 laterally extending torsion bar portion, and attaching end portions on the forward formed portion and on the rear torsion bar. 1

3. A spring strip element made of wire having a central straight wire section with resilient end portions thereon, the forward end portions being coiled into a rectangular spring extending downwardly in a W shape in profile the center of which is aligned with said section and the end of which terminates in an attaching portion.

4-. A spring strip element made of wire having a central straight wire section with resilient end portions thereon, the forward end portion being coiled into a rectangular spring extending downwardly in a W shape in profile the center of which is aligned with said section and the end of which terminates in an attaching portion, the rear section of said spring being formed of oppositely presenting U-shaped loops which slope downwardly from said section and terminate in an attaching end.

5. A spring strip made of wire having a central straight section with resilient end portions thereon, the forward end portion being coiled into a rectangular spring of W shape in profile the center of which is aligned with said section and the end of which terminates in an attaching portion, the rear section of said spring being formed of oppositely presenting U-shaped loops which slope downwardly from said section and terminate in an attaching end, said attaching end extending upwardly at least to the height of said downwardly sloping U-shaped loops.

6. The subject matter as claimed in claim 1 wherein said straight wire section has a bend therein interjacent its ends to provide an upwardly extending arch within the length thereof.

7. The subject matter as claimed in claim 6 wherein said straight wire section extends on the center line of said front and rear formed supporting portions.

8. The subject matter as claimed in claim 1 wherein said formed portion beneath the forward end of said straight wire section is wound into loops extending downwardly in a W shape in profile, and including a formed portion beneath the rear end of said straight wire section and connected to said laterally extending torsion bar portion to provide resiliency to the rear end of the straight wire section said rear formed portion being wound into loops extending downwardly in a Z shape in profile.

References Cited in the file of this patent UNITED STATES PATENTS 423,157 Hubbard Mar. 11, 1890 605,095 Gardiner June 7, 1898 2,265,251 Reed Dec. 9, 1941 2,646,108 Norman July 21, 1953 2,684,844 Flint et a1. July 27, 1954 2,731,075 Flint Jan. 17, 1956 FOREIGN PATENTS 232,3-12- Great Britain Apr. 14, 1925 757,717 Germany Aug. 28, 1952 

